Personnel platforms (sometimes known as "crane baskets" or "man-baskets") are conventionally used with a crane for vertical transportation of workers and equipment to a worksite above ground, an electric power line, for example.
The Occupational Safety and Health Administration (OSHA) is empowered (29 C.F.R. 1926.550) to require a trial lift and proof testing of a crane and its personnel platform at each set-up of the crane immediately before using the personnel platform with workmen in it.
The purpose of the trial lift and proof test (sometimes herein collectively called a load test) is to insure that the personnel platform can be safely used in each work position. Specifically, the load test (1) helps to determine whether the outrigger pads are on firm and even ground and whether the outrigger pads will sink down in the work position selected for use; (2) checks to be sure that the crane is within the 50% of rated lift capacity when in the selected work position; (3) checks to be sure that the load line is working properly and does not fail with the intended load; and (4) checks the four leg bridle to insure that it is capable of lifting the intended load.